Water dispersible ZnSe/ZnS quantum dots: Assessment of cellular integration, toxicity and bio-distribution

Quantum dots (QDs) comprise an emerging group of materials with innumerable number of possibilities in biological research including cellular labelling. Among the leading members in this category, ZnSe/ZnS quantum dots (QDs) hold greater attractive possibilities in imaging primarily due to their higher biocompatibility and dispersibility. Nevertheless, the inherent toxicity of ZnSe/ZnS QDs is not yet completely explored which largely compromise most of their biomedical application potential. Strong blue emitting water soluble QDs effectively synthesized by aqueous phase route. Synthesized QDs further subjected to various optical and physicochemical characterization. Approximately 5-6 nm sized ZnSe/ZnS QDs illuminated bluish green fluorescence under UV lamp. Present study addresses possible adverse effects of ZnSe/ZnS QDs in hepatic system using HepG2 cells; which is the routinely employed in vitroliver cell model. A bundle of assays wasperformed out to reveal the cytotoxic nature of ZnSe/ZnS QDs and the mechanism behind it. Herein, absorption, distribution, metabolism, excretion and toxicity (ADME and T) of ZnSe/ZnS in mice were profiled in detail followed by intravenous (i.v.) and intraperitoneal (i.p.) administration at a dose of 10 mg/kg body weight. In a short review, it could be state that ZnSe/ZnS QDs did not exhibit any significant in vivo toxicity outcome in mice.